Ad Fontes Media is a public benefit corporation headquartered in Westminster, Colorado, best known for the Media Bias Chart, a nonpartisan rating of news sources on political bias and reliability. The company was founded in 2018 by patent attorney Vanessa Otero with a mission to rate news in a way that helps readers identify credible reporting and reduce political polarization. Ad Fontes uses a team of analysts across the political spectrum to score individual articles and overall outlets, and licenses its data to researchers, educators, advertisers, and platforms working on media literacy and brand safety. As a member of the Colorado LGBTQ Chamber of Commerce, Ad Fontes Media serves the LGBTQ+ business community in the Denver metro area.